The invention relates to a data processor which has interrupt in a central processing unit, an interrupt handler which signals a single interrupt vector, and multiple interrupt sources connected to an interrupt handler through a daisy-chain unit to exchange interrupt request signals and interrupt acknowledge signals[]. The interrupt handler communicates a read vector command to all interrupt sources in parallel, to allow transmission of an actual interrupt address vector. In particular, the various interrupt sources may be distributed among a plurality of individual daisy chains.
Interrupt organizations have been around for a long time, but a need for further improvement and extension is still being felt. Such development may lie on various levels of quality and quantity, for which reason the present invention should in particular cater to:
it should support a large number of different interrupt sources and/or interrupt causes, typically 200 or more; PA1 it should support a large number of different priority levels, typically 16 or 32; PA1 it should provide vector support to facilitate fast selection of an appropriate handler routine; PA1 it should be easily extendible in size; PA1 it should allow flexible allocation of interrupt priorities. PA1 it should require only a minimum of routing overhead.
No system has been encountered that is capable of meeting all above requirements at an acceptable price/performance level.